One thing I didn't see brought up in the sibling comments about vapor is that the real hazard of using leaded solder is small particles which can end up on clothing or your hands and later ingested. It is definitely a hazard to be aware of, you want to wash your hands after working with it and keep your workspace cleanliness in mind.

For hobby work, I've switched to lead-free simply because that's what 99% of the boards I work on we're originally soldered with, but I still have some leaded solder around. That being said, it can be used safely, I cast my own bullets which generates a far larger amount of lead particulate and my blood lead levels were not at all elevated when I had them checked 2 years ago. But since it bioacumulates, you do want to keep exposure in mind.